A light output device of the type mentioned by way of introduction is disclosed in the US-patent application US 2006/0274421 A1 (Okamitsu et al.). In particular, in relation to FIG. 1a in US 2006/0274421 A1, there is described a solid state light source comprising a pair of light emitting arrays. The light emitting arrays output light rays which pass directly to a target surface, whereas other rays produce a combined irradiance produced by an optical mixing element on which the other rays are incident. The optical mixing element may be a semi-reflective mirror which substantially splits the emission of the other rays into reflected rays and transmitted rays which are mixed such that they are superimposed on each other.
However, a problem with the solid state light source of FIG. 1a in US 2006/0274421 A1 is that the light rays which pass directly to the target surface contribute to an uneven mixing at the target surface.